The present invention relates generally to mobile supports or towers, and particularly to improvements in such towers of the kind described in my earlier U.S. Pat. Nos. 4,041,974, 3,407,836 and 3,315,921.
For optimized effectiveness, water towers of the character described must satisfy the requirements of the applications in which they are utilized. For example, they must be quite mobile to be easily transported from one site to another. They must be adapted to being landed and erected on roughly cleared ground without auxiliary ditching or hand shoveling. The tower must be capable of erection to a height such that the water tank is elevated sufficiently above ground level to dispose a spout for effective use. The tower should be capable of being quickly erected and collapsible by one person.
The present invention provides fail-safe operation, with minimum possibility of inadvertent lowering or collapsing, by the provision of an hydraulic actuator system and control arrangement for automatically applying appropriate pressures to opposite sides of an elevating actuator and lowering actuators, operable by an operator utilizing a single control, preferably. The control is preferably spring loaded to return to a central position upon release to maintain the system in status quo, thus to prevent collapse or undesired erection. The system essentially avoids hazards and damages resulting from human error or omission.